24-bit block 	10.0.0.0/8 	10.0.0.0 – 10.255.255.255 	16777216 	Single Class A.
20-bit block 	172.16.0.0/12 	172.16.0.0 – 172.31.255.255 	1048576 	Contiguous range of 16 Class B blocks.
16-bit block 	192.168.0.0/16 	192.168.0.0 – 192.168.255.255 	65536 	Contiguous range of 256 Class C blocks.